DESCRIPTIONS OF GENERA AND SPECIES 423 



Last jpair of hearts in XIII. Five pairs of spermathecae in V-IX; they are round 

 and flattened with a long diverticulum terminating in a dilated extremity. Sperm-sacs 

 in XI, XII; the sperm-reservoirs are in X, XI. Spermiducal glands very lolate 

 extending through three segments. Hah. — Island of Mahe. 



A peculiarity of this species is the arrangement of the spermathecae ; the first 

 three pau-s open anteriorly in their segment, the last two posteriorly; it follows, 

 therefore, that segment seven has two spermathecae on each side. This arrangement 

 is found in AUolobopkora transpadana, and A. complanana. The large number of 

 spermathecae is only found in P. violacea (of Perichaetae, s. s.). 



(51) Pericliaeta acystis, Beddakd. 



p. biserialis, Beddaed, P. Z. S., 1890, p. 63. 



Definition. Clitellum,XlV-XFI,witho%it setae. Male pores wide apart ; behind them, on five 



following segments, are papillae occupying a corresponding position. Setae on either side 



of ventral median line much enlarged. Dorsal pores present. Septa VI-IX, thickened. 



Spermathecae absent. Hob. — Luzon. 



This species, of which I am able to give only an incomplete account, was at first 



identified by myself with Pebeiee's P. biserialis ; I do not, however, now think that 



that supposed identity can be maintained. P. biserialis of Peeeiee has two pairs 



of spermathecae, while the present species has none ; as I examined two specimens 



the absence of spermathecae can hardly be regarded as accidental. 



(5a) Perichaeta forbesi, Beddaed. 



p. forbesi, Beddaed, P. Z. S., 1890, p. 65. 



P. sp., Beddaed, Zool. Anz., 1889, p. 534. 



Definition. Length, 2,^0 mm.; breadth, j7,mm. Clifellum, XIV- XVI, with setae on ventral 



side of all segments. Male pores wide apart; on XVII atid on XIX-XXI are a pair 



of papillae. Dorsal pores commence XII/XIII. Septa TII/VIII, X/XII, thickened. 



Sperm-sacs in XII. Egg-sacs in XIF. Spermathecae in Fill, IX. Hah. — New Guinea. 



In both of the two individuals of this species which I have examined, one sperma- 



theca was doubled ; in one case it was the left-hand pouch of the eighth segment ; in 



the other the corresponding pouch of the next segment. The sperm-sacs appear to be 



peculiar; the single pair are attached to the septum xi/xii; above each of these was 



a pedunculated sac, attached separately to the septum, and entirely filled with Gregarines. 



